From prior art, clips are known which are used for treating aneurysms. An aneurysm is understood to be a vasodilatation, especially an arterial dilatation which is colloquially also referred to as “arterial sacculation”. An aneurysm is a spindle-shaped or saccular localized permanent expansion of the cross-section of blood vessels due to congenital or acquired wall modifications.
Surgical clips are used to squeeze the blood vessel, for example the arterial dilatation, shut. In so doing, two clamping legs clamp the walls of the blood vessel onto each other and prevent flow through the blood vessel.
There are existing already numerous surgical clips which are used for this purpose, for example those known from U.S. Pat. No. 4,935,026 A or U.S. Pat. No. 5,368,600 A. In the latter case a spring element of the type of a bending beam (pre-bent in U-shape or circular segment shape) is inserted in the clip. Also the use of half windings inside the clip is known, as taught in DE 43 19 829 C1, for example. There is disclosed a clamp having two legs which include bulges on their outer surfaces. The legs are resilient relative to each other and are interconnected at their foot-side ends. A clamping ring is slipped over the bulge and then forces the two legs towards each other. The clamping ring may include a pin which is used for stabilizing the connection.
A surgical clip consisting of three parts is also known from DE 199 35 418 C2. Accordingly, a surgical clip comprising two clamping arms being pivotal relative to each other about a pivot axis and in a clamping position having a clamping area substantially adjacent each other is disclosed, wherein each of the clamping arms includes a free end and an end provided with a bearing, in both bearings a joint shaft defining the pivot axis being supported, and comprising a tensioning element being associated with the two clamping arms and maintaining the latter biased in the clamping position, wherein the shaft is formed by the tensioning element.
An aneurysm clamp is known from DE 197 23 637 C1, too. There an aneurysm clamp comprising two arms each having a jaw member and an operating leg which are crossing each other is shown, wherein the operating legs are facing each other and are interconnected by a resetting means biasing the jaw members towards each other and the resetting means has a formed flat metal element describing a constant flat curve between the operating legs, the curve at least in portions taking a wave shape or a rectangular shape.
Another aneurysm clip is known from DE 81 29 049 U1. That aneurysm clip includes two legs, the one leg including a recess corresponding to the width of the other leg in a crossing area, wherein a guide bridges said recess and on both sides of the recess is connected to the one leg by spot welding. Said aneurysm clip finally makes use of a 1.5-fold winding.
A surgical clip also known as “ligature clip” is also known from DE 10 2006 031 092 B3. In order to facilitate, in the case of a surgical clip comprising two arms being interconnected by a spring element and each supporting a clamping jaw, the arms including at their outer surface an opening extending transversely to the longitudinal direction of the arms for receiving a projection of a handling instrument, the application of the handling instrument to the clip, it is suggested that the opening is surrounded by a trough-shaped guiding surface which falls from outside toward the opening.
A surgical clip including two clip legs adapted to squeeze a blood vessel shut is known from DE 10 2010 037 468 A1. In detail, a surgical clip is described there comprising two clip legs the free first ends of which fully abut on each other in the closed state of the clip, i.e. in the idle position thereof. The idle position is reached in the state of use, with merely the walls of a blood vessel still being arranged between the clip legs. The two clip legs are formed to cross each other and are connected to each other by their second ends being opposed to the free first ends via a spring element. The spring element is an integral part of the two clip legs and includes one and a half windings.
In the known surgical clips frequently the problem arises that they have to be manufactured by hand, thus preventing efficient use of machines during fabrication. Also fissuring problems, especially caused by the winding of leg springs or the bending of specific clip geometries, are known. When leg springs have been wound so far, undesired over-winding has been possible so far, thus increasing the chance of failures. It has further been difficult so far to exactly adjust the closing force. Adjusting a closing force has not been easy so far. So far, spring overload has not been excluded.
Apart from the drawbacks of insufficient closing force, common surgical clips also have a construction size which is so wide that the view to the aneurysm to be treated is obstructed when the clip is applied. For the aneurysm clamp of DE 197 23 637 C1 only a maximum closing force of 1.76 Newton is known, which corresponds to an equivalent of 180 grams.